Despite assurances to the contrary, the IRS didn’t destroy all of the donor lists scooped up in its tea party targeting — and a check of those lists reveals that the tax agency audited 10 percent of those donors, much higher than the audit rate for average Americans, House Republicans revealed Wednesday.

Republicans argue that the Internal Revenue Service still hasn’t come clean about the full extent of its targeting, which swept up dozens of conservative groups.

“The committee uncovered new information indicating that after groups provided the information to the IRS, nearly one in 10 donors were subject to audit,” Rep. Charles W. Boustany Jr., Louisiana Republican and chairman of the Ways and Means Committee’s oversight panel, told IRS Commissioner John Koskinen at a hearing Wednesday.

“The abuse of discretion and audit selection must be identified and stopped,” he said.

Mr. Koskinen didn’t specifically address the accusations during the hearing, and the IRS didn’t respond to a request for comment late Wednesday evening.